It is known to use free-standing monopoles to, for instance, support power transmission lines and to support antennas, (e.g., cell sites), such as required for cellular telephone. Particularly as regards the latter, even though demand for improved cellular telephone service continues to grow, local zoning laws are becoming increasingly prohibitive as regards new construction. As a result, wireless companies are placing additional antennas on existing towers. While this approach avoids zoning problems, it creates-leads to loading existing monopoles beyond their design capacity.
Various inventors have noted the problem and proposed systems to increase the loading capacity of existing monopoles. For instance, published applications of Harrison, Nos. 2002/0140621 and 2002/20140623 A1, describe the addition of strengthening elements to the exterior surface of a monopole, and suggests that base plate and/or foundation strengthening might also provide benefit.
Another Published Application, No. 2003/0010426, of Lockwood, describes upgrading existing steel monopoles by bonding fiber reinforced polymer materials to existing steel member or component surfaces.
Another Published Application, No. 2003/0205021 of Ryan, describes applying an exo-skeleton of tubular steel rods and adjustable clamps directly in contact with the exterior of previously erected tapered wireless communication monopoles.
Another Published Application, No. 2003/0026923 of Al-Zoubi et al. describes a sleeve system for reinforcing self-standing monopoles at select, predetermined locations. At least one pair of complimentary non-slip Filler is inserted between the monopole and the sleeve.
Another Published Application, by Cash, No. US 2004/0148903 describes applying sleeves to a tower. There are two foundations, one for the tower and one for the sleeves.
Another Published Application, by Brunozzi et al., No. US 2002/0170261 describes use of sectional elongated tubes affixed to a tower by clamping collars.
Another Published Application, by Kopshever, Sr., No. US 2004/0020158 describes the use of collars to sandwich vertical bars to a tower.
Another Published Application, by Hill et al., No. US 2002/0194794 describes the use of sleeves which are secured to a pole to provide enhanced strength.
Another Published Application, by Lockwood et al., No. US 2004/0134161 describes affixing supports to towers by structural adhesive.
A patent to Damiano, U.S. Pat. No. 6,513,299 describes a sleeve secured to a pole by braces.
A patent to Ritz, U.S. Pat. No. 6,453,636 describes the use of sleeves, wherein a second load is attached to the sleeve.
A patent by Ryan, U.S. Pat. No. 6,694,698 describes use of adjustable mounting clamps to secure a plurality of exo-skeleton tubular steel rods to an existing tower.
A patent to Payne, U.S. Pat. No. 6,915,618 describes another reinforcing apparatus for tower monopoles.
Even in view of the known prior art, need remains for additional system and methodology for reinforcing existing monopoles.